class Fish {
   int weight = 1;
}
class Lake {
   Fish fish;
   void setFish(Fish s) {
      fish = s;
   }
   void foodFish(int m) {
     fish.weight=fish.weight+m;
   }
}
public class E {
   public static void main(String args[]) {   
       Fish redFish = new Fish();
       System.out.println(redFish.weight);  //代码1
       Lake lake = new Lake();
       lake.setFish(redFish);
       lake.foodFish(120);
       System.out.println(redFish.weight);  //代码2
       System.out.println(lake.fish.weight);  //代码3
    }
}
